青岛市屠宰场整鸡中沙门菌污染水平定量检测及耐药性分析

目的调查青岛市规模化肉鸡屠宰场屠宰后整鸡样品中沙门菌的污染及抗生素耐药谱分布状况。方法2014年10~12月在青岛市选择2家规模化肉鸡屠宰场,采用胴体漂洗法定量检测3次共采集的141份屠宰后整鸡样品中沙门菌,根据Kauffmann-White表对沙门菌菌株进行血清学鉴定,应用微量肉汤稀释法检测菌株对11种抗生素的耐药性。结果整鸡样品沙门菌总体污染率为74.5%(105/141),污染水平3.6~1 100 MPN/100 g,中位数为43 MPN/100 g;共分离355株沙门菌,血清型分布为肠炎沙门菌220株,印第安纳沙门菌88株和阿贡纳沙门菌19株,以及其他型28株。355株沙门菌分离株的总体耐药率为90.4%(321/355),萘啶酸(NAL)耐药率最高(88.7%,315/355)。220株肠炎沙门菌中219株(99.5%)耐药,6株(2.7%)为多重耐药株,优势耐药谱为奈啶酸(156株)。88株印第安纳沙门菌均耐药,85株为多重耐药株,优势耐药谱为庆大霉素-氯霉素-环丙沙星-萘啶酸-氨苄西林-青霉烷砜/氨苄西林-头孢他啶-头孢噻肟-复方新诺明。19株阿贡纳沙门菌除1株对奈啶酸耐药外,其余18株对所测试11种抗生素均敏感。结论青岛市肉鸡屠宰场沙门菌污染率较高,血清型以肠炎沙门菌、印第安纳沙门菌和阿贡纳沙门菌为主。沙门菌总体耐药率较高,并呈现多重耐药性趋势。

Quantitative determination of contamination and antimicrobial resistance of Salmonella in chicken carcasses in slaughterhouses in Qingdao

To quantitatively investigate the contamination and antimicrobial resistance of Salmonella in chicken carcasses in broiler slaughterhouse in Qingdao.Methods A total of 141 chilled chicken carcasses were collected from 2 slaughterhouses in Qingdao of Shandong Province once a month from October to December in 2014. All samples were enumerated for Salmonella. Presumptive isolates were serotyped according to Kauffmann-White scheme. The antimicrobial susceptibilities of 11 antimicrobial agents against Salmonella isolates were determined by broth microdilution method.Results Overall, 105 samples (74.5%, 105/141) were positive for Salmonella and the median load was 43 MPN/100 g with the minimum value of 3.6 MPN/100 g and the maximum value of >1 100 MPN/100 g. A total of 355 isolates were obtained. Salmonella enteritidis was the most common serovar detected (220 isolates), followed by S.indiana (88 isolates) and S.agona (19 isolates). 90.4% of the isolates were resistant to at least one antimicrobial, and 88.7% (315/355) of the isolates were resistant to nalidixic acid. Of all 220 S.enteritidis isolates, 219 isolates were resistant to at least one antimicrobial, and 2.7% (6/220) were multi-drug resistant. Of all 88 S.indiana isolates, 85 isolates were multi-drug resistant, and the predominant resistant profile was GEN-CHL-CIP-NAL-AMP-SAM-CAZ-CTX-SXT. Of all 19 S.agona isolates, 18 isolates were susceptible to all 11 antimicrobials, while one isolate resistant to NAL.Conclusion The contamination rate of Salmonella in broiler slaughterhouse in Qingdao is high. S.enteritidis, S.indiana and S.agonist were the main serotypes. The overall drug resistance rate of Salmonella was higher and showed multi-drug resistance.